Basically happy, but…

I’m pretty well set with mostly Transparent Gen 5 Ultra speaker cables and Ref pc’s    However, I still have a legacy Syn Research Copper Element RCA between my Chord DAVE and Pathos Heritage MO ii Intgrated.  It was a great cable “in its day” but I’m wondering if an upgrade will have a noticeable impact on my sound.  I would probably go with a used Transparent Gen 5 Reference if I make a change.  Any thoughts?